I have a recurring nightmare that one day, all the world's software developers will be facebook/apple employees and that startups will be limited to the facebook/apple platform, made by facebook/apple subsidiaries, and will only be available to those with a few million to throw at the advertising...
EDIT: If you want to downvote OK, but please also add a comment with an argument to back your beliefs, other than "I think Facebook is evil"
With Faceboook, a lot of unwanted entities get access to personal data. (http://online.wsj.com/article/SB1000142405274870451310457525...)
Also, disabling the "sharing" of all personal information is quite cumbersome in Facebook. (http://www.nytimes.com/interactive/2010/05/12/business/faceb...)
Google does have its drawbacks, but compared to the "social websites" it seems to be the lesser evil.
Also "just" Google may be bigger than you think, e.g. your voice or text mail may end up in a lot of different departments that use it to train algorithms. Remember what happened with their WiFi sniffing.
My default stand is: all big companies are evil and will abuse my data if they need to. Therefore I want to spread the chances of abuse among different companies.
It's wise to be cautious sharing your data with any large company, but not all of them are created equal.
As long as Google starts off with a gentle, opt-in approach (to stem the problems that came from Buzz), I think they'll be successful.